Vinyl dispersion resins are commercially available and find many applications, primarily in the form of fluid suspensions of fine particle size vinyl halide polymers. The vinyl dispersion resins are normally dispersed in plasticizers to form plastisols, or in volatile organic dispersants or thinners to form organosols. These dispersions usually also contain stabilizers, fillers, pigments and the like. When plastisols are heated, as to about 148.degree. C. to about 177.degree. C., fusion takes place and the dispersion forms a homogeneous hot melt that becomes a tough product when cooled to below about 50.degree. C. In organosols, the organic volatiles are removed during fusion by the heat. These vinyl dispersions can be applied to substrates by spread coating, molding, extrusion, spray coating and the like. Particular problems are encountered in both extrusion and spray coating. For many applications it is necessary that the vinyl resins have thixotropic properties, that is, that they provide dispersions having high yield values at low shear rates, and lower viscosities at high shear rates. It has been found difficult to obtain such vinyl resins by polymerization and many techniques have been tried to obtain dispersions with this desireable property. Improved dispersion resins that provide the desired thixotropic properties in vinyl dispersions are needed.